DOT vs. non DOT H4 headlamps?

brittbolen · 07-27-2004, 09:20 PM

Anyone know what the difference between the DOT and Non-DOT H4 headlamps that our host sells is? Same price. Same bulbs? Same performance?

Do the 80w bulbs make a major difference?

Should i replace the relay if I just use the 55/60W bulb?

I want to keep my big bright chrome rings so I was going to just do the H4 lamps and not the whole Euro H4 upgrade.

thank,

Britt

RoninLB · 07-28-2004, 04:06 AM

http://www.danielsternlighting.com/

Wil Ferch · 07-28-2004, 04:38 AM

There are no DOT lights of any kind. Do a search on this bulletin board on obvious keywords. There are Bosch ( aero style complee replacement units as well as Hella H4 replacement for US style sealed beams used before 88 in US
Wil

RoninLB · 07-28-2004, 04:59 AM

the routine sign of the DOT headlights is the alignment tits on the lens. There are Bosch H-4 with tits and non-DOT without tits.

is that what you mean Wil ?

Wil Ferch · 07-28-2004, 06:47 AM

RoninLB:
Actually...no.
My awkward text is to blame...
Both the Bosch aero H4 and the Hella H4 replacement for the US sealed beam units....do not have the external aiming "tits", and both are not DOT certified.....neither is DOT, was my point.
--- Wil

Joe Bob · Joe Bob's Garage

Like any cop will look....

brittbolen · 07-28-2004, 06:57 AM

The pelican catalog lists a DOT approved H4 now...

http://www.pelicanparts.com/catalog/shopcart/911E/POR_911E_lenses_pg1.htm#item1

Hella H4 Halogen DOT-Approved Headlamp, 2 Per Car, 911/912 (1965-73), Each PEL-H4-70477

So the DOT approval seems to mostly involve having something for an aiming machine to grab onto? Not the wattage of the bulbs, or anything else?

Britt

Oldporsche · 07:21 AM

DOT approved H4's? Well yes, just to muddle up the waters.

In 1939, (perhaps some of you were alive) the standard for headlights was enforced. It called for a sealed beam to keep the silverplated reflectors from tarnishing. This is the "DOT Approved" standard headlight that has been sold for years.

To stay within this particular DOT reg (They have a few!) there has been a twin filament bulb headlight H4 replacement headlight developed. This thing is a sealed beam affair with an interior glass envelope cast into the body of the bulb that can contain a H4 replacement halogen bulb. The ones I have seen fit a standard round bulb design as well as the rectangular ones.

These are more expensive than the not sealed replacement lamps that will just take the H4 bulbs. Obviously, the silvering of the reflector would be protected.

So there you have it, another factor to confuse the many.

As for the aiming tits, for my point of view, they are a joke except to the guys at the many "approved" state vehicle inspection stations.

Good luck,
David Duffield

Wil Ferch · 07-28-2004, 07:26 AM

OK....I didn't realize that....

To be US legal, it would have to have the aiming devices, but my fear ( not seeing the picture) is that the lens "cut" or flute design is different too to get a more "US-based" light pattern. Meaning...you're back at square one. Perhaps Pelican can confirm that the "cut" of the lens is the same as the non-DOT. I wouldn't think they're the same...why have two part numbers to stock that otherwise would be the same? Who would purposely want illegal headlights if they performed the same?
--Wil

brittbolen · 07-28-2004, 07:42 AM

Ok, this was silly, so I just called pelican. The DOT approved lamp has a different lens, with the tits. It is also rounder, and has different fluting.

No idea if one is better than the other in turns of beam aim etc...

Britt

RoninLB · 07:51 AM

fwiw,
DOT optics suck imo.

PS: I don't like the limited side light optics of HD systems either..

JmuRiz · JmuRiz's Garage

The non DOT lens thows a lot more light out. I like em!

Oldporsche · 07-28-2004, 07:51 AM

I go along with RoninLB. DOT standards are so low, that in many cases I find them questionable.

I've read the procedure to use those aiming tools with the tits. They have never said something about manufacturing imperfections with the reflector or incorrect positioning of the filament.

The best way I have found to aim headlights is to park in front of a brick wall in the dark. Then you have a neat grid to aim your headlights with.

Good luck,
David Duffield

Wil Ferch · 07-28-2004, 07:52 AM

AHA ! .... If the fluting is different, then the non-DOT is the way to go. The Euro based fluting is superior in optics than DOT certified stuff.
-Wil

red-beard · red-beard's Garage

Quote:

Originally posted by old_porsche

The best way I have found to aim headlights is to park in front of a brick wall in the dark. Then you have a neat grid to aim your headlights with.

Hmmmm. I think you can still get the aiming charts from JC Whitney. In your garage, you tape these to the wall in front of your car and adjust until the high beam is centered in the cross hairs. I think you can make one yourself in a couple of minutes.